Concept definition

template<class Match>
concept CppClingo::Ground::IsMatch =  requires(Match const &m) {
    { m.vars() } -> std::same_as<VariableSet>;
    m.match(std::declval<EvalContext const &>(), std::declval<typename Match::Key>());
    m.eval(std::declval<EvalContext const &>());
    m.signature(std::declval<VariableSet const &>(), std::declval<VariableSet const &>());
    std::declval<std::ostream &>() << m;
}

Detailed Description

Concept for matchable expressions.

A match must support the following:

a vars function to get all variables in the expression,
a match function to match a ground expression and an assignment,
an eval function returning an optional ground expression given an assignment,
a signature function to obtain a signature grouping compatible expressions,
the match must be printable.